man > Crypt::Mac::HMAC(3pm)

Crypt::Mac::HMAC(3pm) User Contributed Perl Documentation Crypt::Mac::HMAC(3pm)

🏷️ NAME

Crypt::Mac::HMAC - Message authentication code HMAC

🚀 Quick Reference

Use Case	Command	Description
Calculate HMAC (raw bytes)	hmac('SHA256', $key, $data)	Returns raw binary HMAC
Calculate HMAC (hex string)	hmac_hex('SHA256', $key, $data)	Returns hexadecimal HMAC string
Calculate HMAC (Base64)	hmac_b64('SHA256', $key, $data)	Returns Base64 encoded HMAC
Calculate HMAC (Base64 URL safe)	hmac_b64u('SHA256', $key, $data)	Returns Base64 URL safe HMAC (RFC 4648)
Object-oriented interface	Crypt::Mac::HMAC->new('SHA256', $key)	Create HMAC object, then add data and call mac()
Verify HMAC	hmac_hex('SHA256', $key, $data) eq $expected_hex	Compare computed HMAC with expected value

Note: Supported hash algorithms include any NAME for which Crypt::Digest::NAME exists (e.g., SHA256, SHA512, etc.)

📋 SYNOPSIS

### Functional interface:
use Crypt::Mac::HMAC qw( hmac hmac_hex );

# calculate MAC from string/buffer
$hmac_raw  = hmac('SHA256', $key, 'data buffer');
$hmac_hex  = hmac_hex('SHA256', $key, 'data buffer');
$hmac_b64  = hmac_b64('SHA256', $key, 'data buffer');
$hmac_b64u = hmac_b64u('SHA256', $key, 'data buffer');

### OO interface:
use Crypt::Mac::HMAC;

$d = Crypt::Mac::HMAC->new('SHA256', $key);
$d->add('any data');
$d->addfile('filename.dat');
$d->addfile(*FILEHANDLE);
$result_raw  = $d->mac;     # raw bytes
$result_hex  = $d->hexmac;  # hexadecimal form
$result_b64  = $d->b64mac;  # Base64 form
$result_b64u = $d->b64umac; # Base64 URL Safe form

📖 DESCRIPTION

Provides an interface to the HMAC message authentication code (MAC) algorithm.

📦 EXPORT

Nothing is exported by default.

You can export selected functions:

use Crypt::Mac::HMAC qw(hmac hmac_hex );

Or all of them at once:

use Crypt::Mac::HMAC ':all';

⚙️ FUNCTIONS

🔑 hmac

Logically joins all arguments into a single string, and returns its HMAC message authentication code encoded as a binary string.

$hmac_raw = hmac($hash_name, $key, 'data buffer');
#or
$hmac_raw = hmac($hash_name, $key, 'any data', 'more data', 'even more data');

Note: $hash_name ... any <NAME> for which there exists Crypt::Digest::<NAME>; $key ......... the key (octets/bytes)

🔑 hmac_hex

Logically joins all arguments into a single string, and returns its HMAC message authentication code encoded as a hexadecimal string.

$hmac_hex = hmac_hex($hash_name, $key, 'data buffer');
#or
$hmac_hex = hmac_hex($hash_name, $key, 'any data', 'more data', 'even more data');

Note: $hash_name ... any <NAME> for which there exists Crypt::Digest::<NAME>; $key ......... the key (octets/bytes, not hex!)

🔑 hmac_b64

Logically joins all arguments into a single string, and returns its HMAC message authentication code encoded as a Base64 string.

$hmac_b64 = hmac_b64($hash_name, $key, 'data buffer');
#or
$hmac_b64 = hmac_b64($hash_name, $key, 'any data', 'more data', 'even more data');

Note: $hash_name ... any <NAME> for which there exists Crypt::Digest::<NAME>; $key ......... the key (octets/bytes, not Base64!)

🔑 hmac_b64u

Logically joins all arguments into a single string, and returns its HMAC message authentication code encoded as a Base64 URL Safe string (see RFC 4648 section 5).

$hmac_b64url = hmac_b64u($hash_name, $key, 'data buffer');
#or
$hmac_b64url = hmac_b64u($hash_name, $key, 'any data', 'more data', 'even more data');

Note: $hash_name ... any <NAME> for which there exists Crypt::Digest::<NAME>; $key ......... the key (octets/bytes, not Base64url!)

🛠️ METHODS

🆕 new

$d = Crypt::Mac::HMAC->new($hash_name, $key);

Note: $hash_name ... any <NAME> for which there exists Crypt::Digest::<NAME>; $key ......... the key (octets/bytes)

📋 clone

$d->clone();

🔄 reset

$d->reset();

➕ add

$d->add('any data');
#or
$d->add('any data', 'more data', 'even more data');

📁 addfile

$d->addfile('filename.dat');
#or
$d->addfile(*FILEHANDLE);

🔐 mac

$result_raw = $d->mac();

🔐 hexmac

$result_hex = $d->hexmac();

🔐 b64mac

$result_b64 = $d->b64mac();

🔐 b64umac

$result_b64url = $d->b64umac();

🔗 SEE ALSO

• CryptX
• https://en.wikipedia.org/wiki/Hmac
• https://tools.ietf.org/html/rfc2104

perl v5.34.0 2022-02-06 Crypt::Mac::HMAC(3pm)